A new version of the Google Daydream View VR headset (to complement the new Pixel phones)

Google does have a 2016 patent for a head-mountable VR device with adjustable transparency. The device could be controlled via cell phone.

The remote device may be any type of computing device or transmitter including a laptop computer, a mobile telephone, or tablet computing device, etc., that is configured to transmit data to the device. The remote device and the device may contain hardware to enable the communication link, such as processors, transmitters, receivers, antennas, etc.

The optical element could include at least one liquid crystal cell, an electrochromic cell, a suspended particle device, and/or a switchable mirror. The optical element could be operable to change the transmittance of the optical element and/or the optics.

Looks like Google is improving the original VR headset in this 2015 patent app so that it can communicate wirelessly with other devices. I'm guessing that would include a smartphone. (HMD is head-mounted device.)

0085] In one example, the HMD may include a wireless communication system for wirelessly communicating with one or more devices directly or via a communication network. For example, wireless communication system could use 3G cellular communication, such as CDMA, EVDO, GSM/GPRS, or 4G cellular communication, such as WiMAX or LTE. Alternatively, wireless communication system could communicate with a wireless local area network (WLAN), for example, using WiFi. In some embodiments, wireless communication system could communicate directly with a device, for example, using an infrared link, Bluetooth, or ZigBee. The wireless communication system could interact with devices that may include, for example, components of the HMD and/or externally-located devices.